19 



Fig. 2A represents a cast of the cranial cavity and orbita of a 

 yoniig Macacus cjnoniolgiis, Fig. 2B tiiose of an adult specinien. 

 A dotted line indicates the location of the eje-ball. When comparing 

 the two figures, the difference between the young and the adult 

 specimen as to «opographical relation of the orbita and consequently 

 of the eyeball, is quite obvious. In the young specimen the eyeball 

 is still subcerebral, in the adult it is on the other hand precerebral. 



The same holds for Siainanga syndactylus, though in a smaller 

 degree than for Macacus, as will be seen in Fig. 3A (young animal) 

 and 3B (adult). Here the anterior displacement of the orbit during 

 growth is not so considerable as with Macacus, which accounts for 



Fig. 4. 



2* 



